Purification of oils



Patented Mar. 19, 1929.

UNITED STATES HENRY ODEEN, 01E PALO ALTO, CALIFORNIA.

PURIFICATION OF OILS.

No Drawing.

This invention has to do with a process of refining oils and oil emulsions and more particularly the refining of fatty oils containing free fatty acids, and in its broader aspect includes the steps of adding to and mixing with such oils a finely divided solid material carrying a dry alkali and adding sufiicient water to promote a rapid neutralization of free fatty acids and to agglomerate the resultant soap stock.

One of the more important features of my invention resides in the employment in the process of a dry reagent hereinafter for brevity, referred to as dry chemical which consists of a finely divided solid material carrying a dry substance, such as a dry alkali, capable of acting upon and neutralizing the free fatty acids of the oil. The finely divided carrier material may be inert and non-absorbent and may be formed, for example, by thoroughly mixing the inert non-absorbent material (which may be) in powdered form with a concentrated solution of the alkali, such as caustic soda, drying the said mixture, and grinding or ulverizing the resulting cake to a relatively ne powder. The surfaces thereof or substantial portions of the particles of powder will therefore be coated with and carry a closely adherent thin film of dry alkali. So formed the dry chemical, when added to the oil, is in an ideal state or condition not only to serve as a scrubber to remove coloring, mucilaginous, colloidal and finely divided Suspended matters but also, when in the presence of water, to enable the reaction between the alkali and the acid components of the oil to proceed with avidity. However, I prefer, for reasons more fully pointed out hereinafter, to employ a finely divided solid material which will absorb and be impregnated with the alkali in the step of forming the dry chemical, and I shall describe my invention in'detail in connection with such a finely divided solid absorbent material impregnated with a dry alkali. My process is also applicable to the refining of fatty oils in which a substantial proportion of fatty acids have already been removed, in which case the alkali carried by the finely divided solid material serves to further purify the oil with respect to its coloring, colloidal, mucilaginous and finely divided suspended matters.

It may be stated at this point that if there 5 Application filed July 14, 1926. Serial No. 122,505.

l 0 I 1 o v is present n the oil, which is rarely the case, a sufiicient or an excess amount of water to satisfy the process then it is only necessary to add to such an oil the dry chemical 111 an amount sufficient to combine with and remove the moisture and other ordinary mpurities from the oil; and by ordinary impurities is meant free fatty acids, coloring, colloidal, mucilaginous and .finely divided suspended matters. aspect my invention, therefore, does not necessarily contemplate the addition of water where a suflicient amount thereof already exists in the oil to be refined. In all cases where water is to be added to the fatty oils, except where it is desirable to leave a colored oil as in the case of salad oils, I prefer to first add and thoroughly mix the dry chemical with the oil to be treated so as to obtain the beneficial results of a previous scrubbing action upon the oil and thereby effect a more complete removal of the coloring, colloidal, mucilaginous and finely divided suspended matters.

The present invention relates to and involves What will herein be termed a dry while water is used in the op- 1 eration, it is practically all absorbed by the process, since,

reaction products and by the dry chemical added. In practice the process involves the use of a limited amount'of watei'flso that it will be within the absorptive capacity of thereaction products, and the use of a dry chemical to produce the reactions and assist in absorbing the Water. Soap is the principal reaction product and this, together with the precipitated coloring, colloidal and finely divided suspended matters is left closely adherent to and entangled with the dry chemical in a substantially solid agglomerated state at the conclusion of the treatment, whereas in the commercial processes heretofore generally used industrially, enough water is present'so that these soaps and similar products existed as liquid solutions at this stage, hence these prior processes can be termed wet processes. It is on account of their solid form and due to the absence of excess water that the said soap products and other impurities are more insoluble in the oil, causing the same to more readily precipitate and be very easily removed in their entirety, from the purified oil in my improved process, and this I consider to be an important achievement. I

In its broadest will now describein detail what I consider to be the preferred embodiment of my invention. e

The present invention specifically contemplates the use of a'dryform of alkali or neutralizing agent (preferably caustic soda oil during the 0 oration (e. g. before, during or after the ad ition of the pulverulent material, but not pre-mixed therewith) to a d and hasten the reaction between the alkali and the acid components in the oil, and also the said limited amounts of water control said reaction so that the action of the alkali is prevented from saponifying any appreciable amount of neutral 'oil but is confined to the neutralization of acidity and the removal of other impurities. If no water were added during the process and only the usual traces of moisture found in crude oils were present, the reaction would be extremely sluggish and would not proceed to completion for a long period of time, but the instant that water makes contact with alkali, the reac-' tion proceeds with avidity and this takes place between the alkali and the acid coinponents because of the latters greater afiinity for alkali than that existing between neutral oil and alkali. Howeverfatty oils are readily saponifiable by caustic alkalies if any considerable amount of moisture is present; therefore in this method the amount of water introduced into the operation is so limited that a substantially dry oil 'is formed, and the soap formed is in a solid (and not, dissolved) state. By thus controlling the reaction a more nearly quantitative separation of acid components can be effected than by using an excess of aqueous solution of alkali which is the common method employed in the practice of the art- A slight excess of free water which or'- dinarily would be present or added during the operation would not be available for the saponification of any substantial amount of neutral oil because of the presence of the dry chemical and reaction products which have dehydrating properties. Even the films of soap which are f rmed in the reaction serve to assist in the ehydration of the oil after the essential reaction has taken place, for the reason that underneath the soapfilm, in the preferred form of my invention, exists a dry absorbent particle containing dry caustic alkali, and the dry alkali itself dehydrates in a powerful way; then there is also the that during the neutralizing operation agi-- tation is employed so that there is uniform distribution of the neutralizing agent throughout the mass of the oil being treated.

Another noteworthy advantage of this method in all of its embodiments is that it v will remove more coloring, mucilaginous, colloidal, and finely divided suspended matters than will the ordinary wet neutralizing methods. This may be partly due to the cauterizing action of" the caustic alkali existing in such active state, and, in my preferred embodiment, partly due to the moreased absorption power, for example, of the fullers'earth, which results in the above mentioned materials being rendered more insoluble and thrown out of their semi-soluble or colloidal state and thoroughly agglomerated much the same as the clarifying action which' takes place in water purification when alum is added.

B the use ofmy method oil-Washing and oilrying equipment is not needed, and the bleaching equipment can be muchsimplified, thus lending to considerable economy in the apparatus used.

The present invention is 'broadl applicable to fatty oils in general, inclu ing those oils which are solid at normal temperature as well as those oils which are liquid at normal temperature, and is also applicable to mineral oil materials containing acids to be removed. The present application will be especially described in connection with normally solid oils (oils or fats that are solids at normal room temperature) of which I mention cocoanut oil, palm oil, .palm kernel oil, tallows of various kinds, includ ing tallows from animals and vegetable sources, etc. The process is also applicable to normally liquid oils such as cotton seed, rape, soy bean, cod liver, lard oils, as well as all kinds of fish oils, and claims specific to the treatment of normally liquid oils are included in m copending application Serial No. 122,504, led concurrently herewith.

The present invention contemplates a distinctively dry process of refining oils, and while water is used and is important inthe process, the absorptive capacity of the absorbent neutralizing agent and solid reaction products, is preferably always greatly in excess of the total amount of water present or added during the process.

As in my priorapplication 727,543, filed July 22, 1924, of which the present case is a continuation in part, fullers earth will be discussed as a typical absorptive material in the dry chemical used. Other absorptive agents, such as kieselguhr, vegetable carbon Anhydrous salts or those partially hydrated and capable of taking up additional water of crystallization, such as sodium carbonate or sodium sulphate can likewise be employed as the carrier for the caustic alkali. Some of these materials, notably sodium carbonate, might be considered as not inert since they might exercise more or less neutralizing action upon the free fatty acids.

As stated, water is employed in the process in amount capable of promoting the reaction between the free fatty acids and the alkali, and ordinarily relatively pure water (e. g. ordinary tap water) is preferred. However, the use of water containing dissolved salts or other dissolved substances is not preeluded. Thus it might be advisable to employ, instead of pure water, solutions of common salt, aluminum sulphate or borax, or other substances which may to some extent precipitate or destroy coloring matter in the oil or which may to a gonsiderable extent assist in dragging down and precipitating colloidal or suspended matters, or albuminous matters or other gummygor mucilaginous substances present in the oil.

The amount of water to be used in the process will vary, .depending largely upon the quantity of free fatty acids present in the oil. With oils of ordinary free fatty acid content (say 3 to 7% freefatty acid content) an amount of water equal to 0.5% u to 2% or 4% or so, will generally be satis actory, although somewhat larger amounts than this may be used if desired. Insome cases commercial crude fatty oils (say cocoanut oil) frequently contain more or less water, say up to 0.7% or even considerably more than this. With oils naturally containing such quantities" of water, and especially if the free acid content is low, it may not be necessary to add further amounts of water during the process. Generally stated, I find it advisable to add more water if the'oil is high in free fatty acid content than would be needed if the oil is low in free fatty acids. Thus with a 5% F. F. A. co-

coanut oil, I may use'about 2% of water,

after the addition of the dry chemical, or can be added during the addition of the dry chemical, but separately therefrom. I do not mix the water with the dry. chemical and add the said mixture to the oil to be treated, since this would be wasteful and I -would not get the complete results of the process. In treating cocoanut oil, and many kinds of similar oils, I preferably-add all the water (aside from that naturally pres-' ent in the crude oil) after the addition of the dry chemical (i. e. the solid absorbent material impregnated with dry alkali) and preferably after well agitating the mixture of the warm liquid oil and dry chemical for a while (say for 10 to'30 minutes, more or less). This is-,because with such oils as are herein particularly referred to, the agitation with the dry chemical considerably reduces the color and removes colloidal mucilaginous and fine suspended matters, which 1s of importance in the treatment of such oils. The modification of adding the water The amount of the dry chemical to be add- I For ordied will depend onnumerous factors, includnary purposes 2 to 5% (based on the amount some cases, particularly where it is desired to produce a considerable amount of decolorization of the oil, I may use 10% or even more.

The. amount of active neutralizing reagent, say caustic soda, should preferablv be in excess of the amouutwhich theoretically would be necessary for combining with andeneutralizing the total free fatty acids in the oil under treatment 'if it is desired to completely remove such acids. An excess of from 50 to over the theoretically required amount of caustic soda is recommended in some cases. The reason for this is that the absorbent material, which is the preferred form of carrier, will contain some alkali undecomposed pr not reacted upon, at the end of the treatment.

The dry chemical which I prefer to use may, for instance, be formed by impregnating a dry inertabsorbent material, suchas of the oil) will be found to be a convenient amount of the dry chemical to use, but in fullers earth or any of those above referred to, with a solution, preferably a highly concentrated solution, of caustic soda, then I dry the so impregnated material, for example in an oven or pan at a temperature of 200 to 800 or to 400 F., or, if desired, much higher temperatures can be used. With 100 parts of ordinary fullers earth, I may (for example) use 130 parts of a saturated (say solution of caustic soda. The material is thereafter dried and the resulting cake is ground up or pulverized to a rela tively fine powder. In other cases,,with 100 parts of fullers earth satisfactory materials have been prepared when using from 80 to 150 parts of saturated caustic soda solution or weaker solutions containing 10-4575 NaOI- I, more or less. Such a dry chemical may be very advantageously employed in refining oils in which a substantial amount of the free fatty acids have already been removed.

I have referred above to drying the 1mpregnated fullers earth, but it is to be understood that this drying does not have to be complete to the extent of removing every trace of water. The material is dried sufficiently so that it will readily absorb and take up water present in or added to the Oll. The term dry will be so understood herem as applied to the impregnated carrier.

Complete impregnation 1n the manner above described followed by drying, gives a satisfactory chemical to use. However in some cases, caustic soda and fullers earth can be well ground and triturated together, say in a mortar or edge-runner mill. ,If the mill is open to the atmosphere the caustlc may take up more or less molsture from the atmosphere during this step, or some water can be added to the mass or to the materials, before or during the grinding andm xmg operation. Thus this will give an intimate association and substantially an impregnation. This product can bethen dried and powdered, as above descrlbed. D

In practising the method of Oll refining and purification in its preferred form, I generally warm up the oil to a temperature at which it is freely liquid and at which it has a sufficiently low viscosity to be readily treated. This temperature will depend upon the particular oil, and with cocoanut 011 a temperature of 110 to 130 F. is verysatisfactory. Irrespective of the particular oil treated (if a fatty oil), I preferably do not heat to over 140 F. at, and above which the heat is likely to set the color and otherwise injure fatty oils. Some water can then beadded, or if desired a portion of th s water can be added at this stage and the balance of it added later. Preferably however, I do not add the water until after the dry chemical has been added to and well agitated with the oil.

of the agitated mass of oil carrying the fine dry chemical in suspension. The break will occur after only a few minutes further agitation. I may add the water from a spray nozzle, said nozzle being adjusted to give a fine spray. 1 preferably watch the oil carefully and when large streaks ofclear oil and large clots of a sponge-like ap earance show in the oil, I then shuto the water inlet, and allow the agitation to continue for a few minutes longer (say 1 to 5 minutes, or more). During this continued agitation, the Water in the oil (i. e. the last of the water added) is absorbed by the solid material, that is, the reaction products and the dry chemical.

Instead of using plain water, in the preceding paragraph, I may use a 5 or 10% solution of common salt, alum or the like. As is well known, common salt acts to render soap less soluble.

The oil and materials contained therein are then preferably allowed to settle and sedimentation will occur quite rapidly even in a large bulk of oil it will be found that the solid matter will practicallyrall settle out of the oil, within half an hour or an hour, and the clear oil in the upper part of the receptacle can then be passed through the filter press (or other separating device) and sent to storage as refined oil. .This settling is more or less optional and the entire mass in the refining tank, say a few minutes after the water is shut off, could be pumped into a filter press or other separating device. The settling and separate removal of the clear oil is an advantage as the larger part of the soap stock does not have to go to the filter press at all.

Due to the powerful drying or dehydrating properties of the dry chemical and the water-absorbing properties of the soap formed, the filtered refined oil will be found to be very bright and clear, and analysis will show practical absence of water therein, or say usually Well below 0.25% and in most cases below 0.1% of water.

The sludge in the bottom of the refining tank can be drawn off and this will carry more or less entrained oil and this latter can be practically all separated from the solid material in a centrifugal basket separator or other suitable device. This oil can then be passed over to the filter press above referred to, thence to the storageriers can be reused many times if desired.

When other solid absorbent chemically inert insoluble carriers such as clays, charcoal,

etc., are employed, the above mode of re generating same for reuse, will be satisfactory. When anhydrous soda or soap powder is used as a carrier, the solid material from which the oil has been removed can be sold as soap stock or worked up into soap products, e. g. by adding resin or more fatty acids if a more nearl neutral soap is desired, and if desired ad ing some water. \Vhen powdered abrasive suehas kieselguhr or pumice is used as the carrier, the solid product separated from the oil can be usefully incorporated into scrubbing powders, etc.

In the process of refining, as herein described, it is generally an object to remove the free fatty acids as completely as possible. However, in some instances, it would be suflicient to use far less than enough of the dry chemical and of Water to accomplish this. Thus a highly colored and highly odoriferous oil might be treated with only enough of the dry chemical and water, to somewhat brighten its color and remove some'of its odorous substances While removing only half or less of its free fatty acid content to cheaply improve a soap-making oil.

In a modified form of the process, I may add somewhat more Water, even continuing the addition of water after the break 1 say while agitating. I can then settle and decant or filter, if desired, although these operations at this stage are unnecessary. I can then suitably remove the excess of water, as by adding more of the alkaline absorbent reagent, or other water-absorbing substance, followed by a short agitation and filtration. This modification may sometimes produce more bleaching or more complctc removal of colloidal or suspended matters. but is not generally recommended.

In another modification of the process, I can add alternately several small amounts of water and of the dry chemical, while agitating, until the desired amount of purification has been effected, and the oil may or may not be filtered, say after each addition of chemical has had a chance to act. In this way, a minimum amount of chemical would effect a maximum amount of purification. Such a modification however might cost more in the way of added handling, filtering, etc. The total amounts of water and dry chemical used in this modification may be the same as in the above examples, or less, and the two materials are added alternately in small amounts at a time. The operation is otherwise the same as above. I

I have referred above to the use of caustic soda as the preferred neutralizing agent.

Other alkalies such as the carbonates, oxides and hydroxides of the alkali metals and the alkaline earth metals, or ammonia gas, or salts of weak acids which give a basic reaction, such as borates, silicates, or other agents capable of neutralizing free fatty acids, can be used.

I-have also referred to the use of strong solutions of alkali for impregnating the absorbent carrier materials. In some cases, however, relatively weak solutions or impregnation with only a small amount of alkaline solutions may be advisable. Thus I may prepare dry chemical containin only 2 to 10%, more or less, of N aOH, whic would be very suitable when it is more especially desired to accomplish decolorization, precipitation of colloidal matters, etc., with only a small amount of neutralization of free fatty acids, as when treating oils in which the fatty acid content is quite low. A special example of this is the treatment of cocoa fat from which it is desired to remove a large amount of coloring matters, colloidal and suspended matters, etc., although the free fatty acid is usually very low. For ordinary purposes, however, as

where the removal of a normal fatty acid content is desired, the amount of NaOH in the dry chemical may be higher, say from 10% up to 45%, more or less.

In one of the above examples, I have discussed the drying of, the impregnated absorbent, e. g. fullers earth. When soap powder is used as the absorbent, I may make methods of refining this neutral oil loss is riall one of the greatest, and oftentimes the greatest item of refining cost, but by my method this item of refining cost is matereduced. (b) The absorption losses in t e bleaching and filtering step of the --wet process methods are reduced to a fraction thereof because in my method the clear the number of oil from the refining tank maybe run directly to the filter presses without the addipared with other purification processes) begreater yield xof neutral oil.

cause of less labor and equipment required to carry on the process, and because of a (d) A further substantial reduction in cost and simplification of thewhole process is effected by the decolorizing action taking place in the same stage with the neutralization of the free fatty acids. '(e) A great saving in time is effected, since washing and settling processes are eliminated. to subject the oil to high drying temperatures, thereby insuring a better quality of oil, particularly when the same is to be used for edible purposes. (g) It practically precludes the formation of free fatty acids in the oil under treatment since the oil during processing does not encounter the usual washing and high heating steps. (71.) The neutral oil is practically completely freed of soap in.one operation. (2') Thefworkin up of the soap stock is simplified because 0 the practical absence of emulsions, which are always a source of largerefining loss, and cost of, handling. (j) The process presents es ecial value in the treatment of certain oi s, such as castor oil, which, when subjected to the wet neutralization methods, produce very troublesome emulsions or solutions, or both, in the refining kettle. My process completely eliminates the formation of such emulsions and solutions.

I have described in detail several embodiments of my invention but it is to be expressly understood that I do not limit myself thereto or to the details related in connection with the specific embodiments de-, scribed. I have also indulged in some theoretical discussions of what actually takes place in the practical use of my invention to more clearly elucidate the-principles thereof. I may be mistaken about some of these theoretical considerations but I do know that when the steps of the process are carried out in the manner clearly indicated, nodifiiculties will be encountered in practicing my method and that substantial results, some of which have been referred to, will be achieved.

) It becomes unnecessary plastic mass.

fineness of Portland cement.

oer

above referred to, .well agitated, andfiltered or centrifuged.

I have above referred to dry soap as the carrier in the dry chemical. start with the normally solid soap product produced in the present process, which may contain about 50% of water and about 50% of actual soap. Put an amount of this into a steam jacketed kettle, heat to liquefaction, add about an equal amount of flake or powdered caustic soda, stir until a homogeneous mass is formed, cool to solidification, comminute or powder to as fine a state of division as possible. This may or may not be further dried, and constitutes a suitable example of a dry soap-and-caustic-soda reagent. Add 1 to 10% of this to the oil at say to 100 F., agitate for a short time. add about 1 to 10% of-water, continue agitation,, settle and complete the process as above.

The soap stock in this case would consist of impure soap containing about 40-60% (more or less) of water, .and some free caustic soda and some free oil, suspended matters, etc., and may be sold to the soap industry as such.

As above stated, anhydrous salts can be used as the vehicle. Anhydrous soda, (e. g. soda ash) may be mentioned. I ma mix 100 lbs. of dry soda ash with 150 l s. of hot caustic soda solution of 66% strength. Dry this, while grinding, in a vacuum drier.

Thus I may" This, product can be used and the residue disposed of as in the previous example.

In the above I have referred to using various clays instead of fullers earth.

For example I mix 30 parts of powdered clay with 20 parts of water to make a fairly Tothis I add a hot solution of caustic soda containing 12 parts of NaOH and 6 parts of Water. I then mix the entire mass Well and dry and grind to about the I I add to cotton seed 011 1.5% of this powder (based on the weight of the oil) stir well for 15 minutes, add 1.5% of water, again stir well for 15 minutes, then add another 1% of the dry powder, again stir to thoroughly mix, then add about 1.5% of-water, again stir for 15 to 30 minutes and filter or separate by other suitable means. This oil so treated is practically neutral and of greatly improved color and flavor and is clear and dry, and

practically entirely free of soap and other impurities.

What I claim and desire to secure by Letters Patent is:

1. In a process of refining a fatty oil whose fatty acids have not previously been removed, and of which the water content is below 4%, the steps which comprise adding to such oil a finely divided solid absorbent material impregnated with a dry alkali and separately adding a sufficient amount of water to promote a rapid neutralization of fatty acids and to agglomerate the soap stock without causing appreciable emulslfication, the water being absorbed by the solid material and solid reaction products ielding an oil which is substantially anfiydrous. v

2. In a process of treating fatty oil the steps of adding to such an oil, a finely d1- vided solid absorbent material impregnated with a dry alkali and having present at some stage of the treatment a sufficient amount of water to promote rapid reaction between the said alkali and acid components of the oil, such amount of water being sufficient to agglomerate the resulting products of such reaction without causing appreciable emulsification, the water being absorbed by the solid material and solid reaction products yielding an oil which is substantially anhydrous.

3. In a process of refining a fatty 011 the steps of adding to such oil, while warm, a finely divided solid material carrying-1ntimately mixed therewith a dry alkali there being sufficient water present at some stage of the process to promote rapld reaction between the alkali and acid components and r to agglomerate the resultant reaction prodnets and thereafter separating the insoluble materials from the oil without caus ng appreciable emulsification, the'water belng absorbed by the solid material and solid reaction products yielding an oil which is sub; stantially anhydrous.

4. In a process of refining fatty OllS for neutralization of the fatty acids and dccolorization of the oil, the steps of adding thereto a finely divided solid absorbent ma terial impregnated with a dry alkali and agitating the mixture and separately addlng at some stage of such treatment, water 1n an amount sufiicient to promote a rapld reaction between the alkali and fatty acids and to agglomerate the resulting reaction productswithout causing appreciable emulsification,

'the water beingabsorbed by the solidmaterial and solid react-ion products yielding an oil which is substantially anhydrous.

5. The process ofrefining fatty oil whose acids have not previously been removed and which oil contains coloring matter colloidal and finely divided suspended matter, which process comprises adding to and agitating the particles ofwhich carry a dry .alkali intimately bonded thereto, and separately adding water at some stage of the process, to cause by such steps a precipitation of coloring matter, colloidal and finely divided suspended matter and a neutralization of the fatty acids, the amount of such water being sufficient to promote a rapid neutralization of the fatty acids and agglomeration of the resultant-insoluble products without causing appreciable emulsification, the water being absorbed by the solid material and solid reaction products yielding an oil which is substantially anhydrous and thereafter reinoving the insoluble material from the o1 7 v 6. In a process of refining fatty oils containing free fatty acids and some water, the steps of adding to and mixing with such an oil a dry finely divided solid material carrying a dry alkali in an amount sufficient to remove the water and other impurities from the oil, and thereafter adding sufficient additional Water to promote rapid neutralization of the oil and to agglomerate the resultant soap stock.

7. A process of refining fatty oils containing free fatty acids, which consists only in the sequential steps of adding to and mixing with such an oil a dr finely divided solid material carrying intimately incorporated therewith a dry alkali, adding sufficientwater to promote rapid neutralization of the oil and to agglomerate the resultant soap stock, and thereafter separating the insoluble materials from the oil.

8. A process of refining fatty oils containing free fatty acids, which includes the steps of adding to and mixing with such an oil a finely divided solid soap carrying a dry alkali, and at some stage of the process adding sufficient water to promote rapid neutralization of the oil and to agglomerate the soap that was added and the soap that is formed in the reaction.

9. In a process of refining a fatty oil'con'- taining free fatty acids. the improvement which includes mixing such oil with a f nely divided dry solid material inert to alkali, carrying a dry solid alkali in an amount sufficient to neutralize such free fatty acids, and adding to such mixture only a sufficient amount of water to promote rapid neutralization and to agglomerate .the resultant soap stock without leaving 3 substantial amounts of the soap stock in solution.

10. In a process of refining a fatty oil containing free fatty acids, the improvement which includes mixing such oil with a finely divided dry solid material carrying a dry solid alkali in an amount'sufficient to remove coloring, mucilaginous, and finely suspended matters and to neutralize such free fatty acids, and adding to and agitating with-such mixture only a sufiicient amount of water to promote rapid neutralization and to agglomerate the resultant soap stock.

11. In a process of refining a fatty oil containing free fatty acids, the improvement which includes mixing with such oil a finely divided solid absorbent material impregnated with a dry alkali, said alkali being in amount in excess of that theoretically required to neutralize such free fatty acids, and adding to such mixture a sufiicient amount of water to promote rapid neutralization and to agglomerate the resultant soap stock, but not sufficient. to dissolve any substantial portion of said soap stock.

12. In a process of refining a fatty Oll containing free fatty acids, the improvement which includes mixing with such oil a dry finely divided solid material intimately mixed with a dry alkali, said alkali being in amount in excess of that theoretically required to neutralize such free fatty acids,

and adding to such mixture a sufficient,

amount of water to promote rapid neutralization and to agglomerate the resultant soap stock, but not sufficient to dissolve any substantial amount of said soap stocksuch operation being conducted at a temperature at which the oil is freely liquid, but below 140 F.

13. In a process of refining a fatty oil containing free fatty acids, the improvement which includes mixing such oil with a finel divided solid material carrying a dry alkall, and adding to and agitating with such mixture only a sufficient amount of water to promote rapid neutralization and to agglomerate the resultant soap stock.

14. In a process of refining a fatty oil from which the free fatty acids have not been removed, the improvement which includes warming the oil sufliciently to render the same thoroughly liquid, mixing such warm oil with a dry form of alkali carried by the surfaces and in the pores of a solid, finely divided, material of a porous absorbent nature,.the alkali being present in an amount sufficient to remove coloring, mucilaginous, and finely suspended matter and to neutralize such free fatty acids, and adding to and agitating with such mixture a sufficient amount of water to promote rapid neutralization and to agglomerate the resultant soap stock.

15. A process of refining a fatty oil containing free fatt acids, which comprises adding to and mixing with such oil, while warm enough to be freely liquid, a finely divided solid material carrying a dry substance in intimate contact therewith which substance is capable of acting upon and neutralizing such free fatty acids, moisten:

ing with water and agitating the mixture of such 011 and SOllCl material suiiiciently to promote rapid neutralization and to agglomerate the resultant solid impurities, and thereafter separating the solid impurities from the purified oil.

16. In a process of refining a fatty oil containing free fatty acids, the steps which lnclude forming awarm mixture of such oil and a dry finely divided solid absorbing material carrying in intimate contact therewith, a dry fixed alkali, and moistening such mixture with water whereby soap is formed from the fatty acid and alkali.

17. Ina process of refining a fatty oil containing free fatty acids, the steps which include mixing with such oil a dry finely divided solid material the particles of which carry intimately bonded thereto, a dry fixed alkali in an amount sufficient to combine with such free fatty acids, and moistening said mixture .with water, whereby soap is formed from the fatty acidand alkali;

18. In a process of refining a fatty oil containing free fatty acids,the steps which include mixing with such oil a dry finely divided solid material, the particles of which carry intimately bonded thereto a dry fixed alkali in an amount sufiicient to combine with such free fatty acids, and adding a small percentage of water to said mixture, the total amount of water present, including that added, being insufficient to leave a ,substantial amount of the soap in a dissolved state.

19. In a process of refining a fatty oil containing free fatty acids, the steps which comprise adding to such oil a dry finely divided solid material intimately mixed with a dry fixed alkali and thereafter adding an aqueous material chemically inert' to caustic alkali capable of hastening the reaction between'the free fatty acids and the alkali, the amount of water in such aqueous material being insufficienttoleave any substantial amount of soap in solution.

20. A process of refining normally solid fat containing free fatty acids, which compr ses the steps of melting the fat and adding thereto, while in a freely molten state, a dry finely powdered reagent carrying a dry caustic alkali intimately bonded to a solid bulking agent by drying a solution of caustic alkali on said bulking agent and well agitating the mixture of such oil and alkalized reagent,

21. A process of refining normally solid fat containing free fatty acids which comprises the steps of adding thereto, while in a freely molten state, a dry finely divided solid material carrying a solid dry alkali intimately bonded thereto, and separately adding a small amount of water sufficient to produce a rapid break but insufficient to leave the major part of the soap stock in solution.

22. A process of purifying and deacidifyof free fatty acids, while sai in a normally solid fatty oil which compl'lSeS adding thereto while said oil is molten, a dry solid carrier intimately admixed with a caustic alkali, and separately from such step, adding enough atllueous liquid compatible with caustic alkai to cause the alkali to react with free acids in the oil, the amount of such aqueous liquid so added being insufficient to leave the major part of the soap produced, in solution.

23. A process of purifying and deacidifying cocoanut oil containing not over 10% oil is in a molten state, which comprises adding a sub stantially dry solid carrier intimately associated with caustic alkali, the amount of such alkali being more than chemically equivalent to the free fatty acids in the oil treated, and separately therefrom adding such an amount of water as will hasten the reaction between such alkali and the free fatty acids in the oil and also will be taken up by the said absorbent carrier, excess of alkali used and soap formed, to leave the soapformed in the solid state.

24. A process of purifying and deacidifying normally solid fat, which comprises treating molten normally solid fat containing free fatty acids with about 2 to 10% of a dry reagent, such dry reagent comprising a solid material carrying intimately incorporated therein, a caustic alkali, and separately with enough water to produce a rapidbreak, the amount of such dry reagent being always suflicient, in conjunction with the soap produced, to absorb the entire amount of water present in the fat and added, and the caustic alkali in said dry reagent added being in excess over the amount theoretically necessary to neutralize all the free fatty acids present in said fat, such water and dry reagent being added separately but in any desired order, and the fat being at not above 140 F.,' during such treatment, and agitating the mixture.

25. A process of purifying and deacidifying a fatty oil which comprises treating a fatty oil containing free fatty acids with about 2 to 10% of a dry reagent, such dry reagent comprising a solid absorbent material carrying intimately incorporated there in, a caustic alkali, and with enough water to produce a rapid break, the amount of such dry reagent being always sufficient, in conjunction with the soap formed, to absorb the entire amount of water present in the oil and added, and the caustic alkali in said dry reagent added being in excess over the amount theoretically necessary to neutralize all of the free fatty acids present in said oil, such dry reagent and Water being added separately and in the order here stated, and agitating the mixture.

In testimony whereof, I have hereunto set my hand this 13th day of July, 1926.

- HENRY ODEEN. 

